This invention relates to a method of lowering blood uric acid levels in a mammal by use of certain derivatives of benzothiazolyl oxophthalazinyl acetic acid.
Benzothiazolyl oxophthalazinyl acetic acids are disclosed in European patent publication 222,576 for use in the treatment of chronic complications arising from diabetes mellitus. The use of these benzothiazolyl oxophthalazinyl acetic acids for lowering blood uric acid levels in mammals and for treatment of gouty arthritis in mammals is not disclosed.
U.K. patent publication 2,201,343 refers to the use of 3-(4-bromo-2-fluorophenyl)-4-oxo-3H-phthalazin-1-ylacetic acid in lowering blood uric acid levels. The reference discloses many diseases in which lowered blood uric acid levels occur such as gout, gouty arthritis, pneumonia, certain blood diseases such as myeloid leukemia and pernicious anemia, and renal diseases. The reference does not disclose the use of the present derivatives of benzothiazolyl oxophthalazinyl acetic acid.